Ad Volume Guard for Chrome
Ads that are 2-3x louder than your content? Hearably detects sudden volume spikes using rolling RMS analysis and smoothly clamps them down before they hit your ears.
Real-time enhancement via extension · Or upload a file for free in Studio
It is one of the most universally frustrating experiences on the internet: you are watching a video, listening to a podcast, or streaming music at a comfortable volume, and then an advertisement blasts at two to three times the loudness. You scramble for the volume control, lower it, and then when the content resumes, you cannot hear it anymore because the volume is too low. This cycle repeats dozens of times per browsing session, and it has persisted for over a decade because advertisers deliberately master ads louder to grab attention.
In broadcast television, the CALM Act (Commercial Advertisement Loudness Mitigation) was enacted in 2012 to regulate commercial volume. But the internet has no equivalent regulation. Streaming platforms, websites, and ad networks are free to serve audio at any loudness level. Some platforms (like YouTube) apply normalization to their own content but not to pre-roll and mid-roll ads served through their ad network. Others make no effort whatsoever. The result is a loudness wild west where ads routinely peak at 6-12 dB louder than the surrounding content.
Hearably's Ad Volume Guard addresses this with a real-time volume spike detection and clamping system. The feature continuously monitors the audio output of each tab using a rolling RMS (Root Mean Square) average — a measure of perceived loudness over a sliding window. When the current RMS exceeds the rolling average by more than a configurable threshold (default: 6 dB), the system interprets this as a volume spike — likely an ad or promotional bumper — and applies smooth gain reduction to bring the level back in line with the surrounding content.
The gain reduction is not instantaneous (which would cause an audible click) and not a hard clip (which would cause distortion). Instead, the guard applies a linear ramp over 20-50ms, smoothly reducing the gain to match the target level. When the spike ends and the audio returns to normal levels, the gain smoothly ramps back up over a similar window. The listener experiences consistent volume throughout — content, ads, bumpers, and transitions all play at approximately the same perceived loudness.
This is fundamentally different from an ad blocker. Ad blockers prevent ads from loading entirely, which breaks many websites, triggers anti-adblock walls, and raises ethical concerns about content creator revenue. Hearably's Ad Volume Guard does not block ads — it simply ensures they play at the same volume as everything else. The ad still plays, the creator still earns revenue, and your ears are protected. It is a volume normalizer, not a content blocker, which makes it compatible with every website and every ad network without any cat-and-mouse detection arms race.
How Volume Spike Detection and Clamping Works
The Ad Volume Guard operates as a stage in Hearably's DSP chain, positioned after the input gain and before the main EQ and compressor. It maintains a rolling RMS window — a circular buffer of RMS values computed over the last 2-5 seconds of audio. This window represents the "normal" loudness baseline for the current content.
For each audio processing block (128 samples at 44.1 kHz, approximately 2.9ms), the system computes the instantaneous RMS and compares it against the rolling average. If the instantaneous RMS exceeds the average by more than the spike threshold (configurable, default 6 dB — a 2x perceived loudness increase), the guard triggers. The system calculates a gain reduction factor: targetGain = rollingRMS / instantaneousRMS, which brings the spike back to the baseline level.
The gain factor is applied via linearRampToValueAtTime() with a 20-50ms ramp to avoid clicks. Critically, the rolling RMS buffer freezes during an active spike — the loud ad audio is not incorporated into the baseline average, which would gradually "accept" the higher level and stop clamping. The buffer only resumes updating when the instantaneous RMS returns to within 3 dB of the pre-spike average. A hysteresis mechanism (separate engage and disengage thresholds) prevents rapid cycling when audio oscillates near the threshold boundary. The entire computation is branch-free arithmetic on 32-bit floats, adding zero allocations and under 0.1ms latency to the processing chain.
How to get the best audio on Ad Volume Guard for Chrome
Enable Ad Guard on streaming sites
YouTube, Twitch, Crunchyroll, and free streaming platforms are the worst offenders for loud ads. Enable Ad Volume Guard on these tabs and the volume difference between content and ads virtually disappears. Ads still play — they are just the same volume as everything else.
Works alongside ad blockers without conflict
If you use an ad blocker like uBlock Origin, some ads still slip through. Ad Volume Guard catches these remaining volume spikes. The two tools operate at different levels (network vs. audio) and do not interfere with each other.
Adjust the spike threshold for your tolerance
The default 6 dB threshold catches spikes that sound roughly twice as loud. If you want tighter volume consistency, lower the threshold to 4 dB. If the guard is triggering on natural dynamics in music (loud choruses after quiet verses), raise it to 8 dB.
Combine with Night Mode for maximum consistency
Night Mode applies multiband compression to reduce dynamic range, and Ad Volume Guard catches sudden spikes. Together, they provide the most consistent listening experience possible — especially useful for late-night browsing when volume swings are most disruptive.
Protects hearing during headphone use
Sudden loud ads through headphones can cause actual hearing discomfort and, over time, damage. Ad Volume Guard is a hearing protection feature as much as a comfort feature — it ensures no sudden volume spike exceeds your chosen listening level.
Not an ad blocker — no ethical concerns
Hearably does not block, skip, or hide ads. Content creators still earn ad revenue. The guard simply normalizes the volume so ads are not louder than the content. This is the digital equivalent of the CALM Act that regulates TV commercial volume.
Works on podcast platforms with mid-roll ads
Podcast players in the browser (Spotify Web, Apple Podcasts web, Pocket Casts) often insert dynamically served mid-roll ads at higher volume than the podcast audio. Ad Volume Guard detects these transitions and clamps them in real time.
Built for this exact use case
Real-Time Spike Detection
Rolling RMS analysis continuously monitors audio loudness. When a spike exceeds the baseline by 6+ dB, the guard engages in under 50ms — fast enough to catch the attack of even the most aggressive ads.
Smooth Gain Clamping
No hard clips, no distortion. Gain reduction is applied via a smooth 20-50ms linear ramp. The ad plays at normal volume — you barely notice the transition. When the ad ends, gain smoothly returns to 1.0.
Frozen Baseline During Spikes
The rolling RMS buffer freezes during active spikes so loud ads do not shift the loudness baseline upward. The guard maintains a true reference of what normal content sounds like, even during extended ad breaks.
Compatible with All Other Features
Ad Volume Guard runs as a stage in the DSP chain and works seamlessly with volume boost, EQ, compression, and noise gate. Loud ads are clamped, then the clean signal flows through your chosen processing.
Choose your method
Different situations call for different tools. Hearably gives you both.
Chrome Extension
Enhance audio live while you stream. The extension intercepts your tab's audio and processes it in real-time — volume boost, EQ, presets — without downloading anything.
- Streaming on Ad Volume Guard for Chrome, Netflix, Spotify
- Video calls on Zoom, Meet, Teams
- Any website with audio
- When you want instant, always-on enhancement
Free Online Studio
Upload an audio or video file, apply volume boost + 10-band EQ, preview in real-time, then download the enhanced WAV. Your file never leaves your browser.
- Downloaded videos or music files
- Podcast episodes you want to boost before sharing
- Voice recordings, lectures, interviews
- When you need a permanently enhanced file
Pro tip: Use a YouTube-to-MP3 tool to download the audio, then enhance it in Hearably Studio with EQ + volume boost. Perfect for offline listening, DJ sets, or sharing on social media.
Three clicks to better audio
Install
Add Hearably from the Chrome Web Store. Under 300KB, installs in seconds.
Enhance
Click the Hearably icon and tap "Enhance." Boost kicks in instantly.
Enjoy
Adjust volume, EQ, and presets. Works on any website with audio.
Frequently asked questions
Does Ad Volume Guard block ads?
No. Hearably does not block, skip, or hide any ads. The ads still play and content creators still earn revenue. Ad Volume Guard only adjusts the volume of audio spikes so ads play at the same perceived loudness as the surrounding content.
How fast does it react to a volume spike?
The guard detects spikes within one processing block (~3ms) and applies gain reduction over a 20-50ms ramp. Most listeners do not perceive the brief initial spike — the transition is too fast and the ramp prevents any audible click or artifact.
Will it affect the dynamics of music or movies?
The default 6 dB threshold is calibrated to catch ad-level spikes while leaving musical dynamics intact. A loud chorus after a quiet verse is typically 3-4 dB louder — below the threshold. If you listen to highly dynamic classical music, you may want to raise the threshold to 8-10 dB or disable the guard on music tabs.
Does it work on YouTube pre-roll ads?
Yes. YouTube pre-roll and mid-roll ads are audio from the same tab, so Hearably processes them through the same DSP chain as the video content. If the ad is louder than the video, the guard clamps it.
How is this different from the multiband compressor?
The compressor reduces overall dynamic range (making quiet parts louder and loud parts quieter). The Ad Volume Guard specifically targets sudden loudness jumps that exceed a threshold — it is a spike detector, not a continuous dynamics processor. They complement each other: the compressor evens out normal dynamics while the guard catches extreme spikes.
Does it work on Twitch ads?
Yes. Twitch inserts video ads that are often mastered louder than the stream audio. Ad Volume Guard detects the loudness jump when an ad starts and smoothly reduces gain. When the stream resumes, gain returns to normal.
Can I adjust the sensitivity?
Yes. The spike threshold is configurable. Lower values (4 dB) provide tighter volume consistency but may trigger on natural dynamics. Higher values (8-10 dB) only trigger on aggressive volume spikes. The default 6 dB works well for most content.
Does this add latency?
Under 0.1ms. The RMS computation is simple arithmetic on the existing audio buffer — no look-ahead is needed because the gain ramp starts after detection, not before. Combined with the rest of Hearably's DSP chain, total latency remains under 10ms.